84 LAB REPORT KRIX NEUPHONIX AE40 LOUDSPEAKERS LABORATORY TEST REPORT Graph 1 shows the frequency response of the Neuphonix AE40 as measured by Newport Test Labs. Overall, the ±3dB frequency response extended from 45Hz to 40kHz, which is an astoundingly good result, however, between 200Hz and 20kHz, it was even better again, varying by only ±1.5dB between these two frequencies. This is a superbly flat response. As you can see it’s also linear, so that the response doesn’t ‘tilt’ in such a way that it favours either the bass or the treble. There is, however, a slight lift in the low frequencies that puts the bass at around 100Hz around 1.7dB higher than the midrange. This has the effect of extending the low-frequencies somewhat, which means that although the bass response of the Neuphonix AE40 is 1.5dB down at 45Hz, there’s useful output right down to 35Hz. At high frequencies, the Neuphonix AE40’s tweeter is virtually flat out to 20kHz, after which its output rises to peak at +3dB at 35kHz, before rolling off to the measurement limit of 40kHz (this frequency being the limit of the measuring microphone’s calibration, rather than the upper limit of the tweeter itself). The high-frequency response of the Neuphonix AE40 is shown in greater detail in Graph 2, by virtue of ‘stretching’ the graph and starting the response at 700Hz. This serves only to reinforce the picture of the superb flatness of the AE40’s high-frequency response. The slight dip at 5.5kHz without the grille fitted would be completely inaudible, as would the slight dip in response at 15kHz when the grille is in place. 20 Hz 50 100 200 500 1K 2K 5K 10K 20K dBSPL 40 45 50 55 60 65 70 75 80 85 90 95 100 Newport Test Labs Graph 6. Composite response plot. Red trace is output of bass reflex port. Dark blue trace is anechoic response of bass driver. Light blue trace is sine response of midrange driver. Black trace above 2.5kHz is the gated anechoic response, and below 2.5kHz the averaged in-room pink noise response. [Krix Neuphonix 40th Anniversary Limited Edition Loudspeaker] 10 Hz 20 50 100 200 500 1K 2K 5K 10K 20K 40K Ohm 3 4 5 6 7 8 9 10 20 30 40 50 60 Deg -180 -150 -120 -90 -60 -30 0 30 60 90 120 150 180 Newport Test Labs Graph 4. Impedance modulus of left (red trace) and right (yellow trace) speakers plus phase (blue trace). Black trace under is reference 5-ohm calibration resistor. [Krix Neuphonix 40th Ann LE] 700 Hz 1K 2K 5K 10K 20K 40K dBSPL 40 45 50 55 60 65 70 75 80 85 90 95 100 Newport Test Labs Graph 2. High-frequency response, expanded view, with grille in place (black trace) and with grille removed (red trace). Test stimulus gated sine. Microphone placed at one metre on-axis with dome tweeter. Lower measurement limit 700Hz. [Krix Neuphonix 40th Ann Limited Edition Loudspeaker] 10 Hz 20 50 100 200 500 1K 2K 5K 10K 20K 40K Ohm 3 4 5 6 7 8 9 10 20 30 40 50 60 Graph 5. Impedance modulus showing individual impedances of low-frequency (red trace); midrange (green trace) and high-frequency (light blue trace) plus overall impedance (black trace) of left-channel speaker only (from Graph 4).[Krix Neuphonix 40th Anniversary Limited Edition.] Newport Test Labs 20 Hz 30 40 50 60 70 80 90 100 200 300 400 500 600 700 800 dBSPL 40 45 50 55 60 65 70 75 80 85 90 95 100 Newport Test Labs Graph 3. Low frequency response of front-firing bass reflex port (red trace), woofer(s) (black trace) and midrange driver (green trace). Nearfield acquisition. Port/woofer/mid levels not compensated for differences in radiating areas. [Krix Neuphonix 40th Ann Limited Edition Loudspeaker] 20 Hz 50 100 200 500 1K 2K 5K 10K 20K 40K dBSPL 40 45 50 55 60 65 70 75 80 85 90 95 100 Newport Test Labs Graph 1. Frequency response. Trace below 2.5kHz is the averaged result of nine individual frequency sweeps measured at three metres, with the central grid point on-axis with the tweeter using pink noise test stimulus with capture unsmoothed. This has been manually spliced (at 2.5Hz) to the gated high-frequency response, an expanded view of which is shown in Graph 2. [Krix Neuphonix 40th Anniversary Limited Edition Loudspeaker]